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  <h1>Source code for nlp_architect.utils.file_cache</h1><div class="highlight"><pre>
<span></span><span class="c1"># ******************************************************************************</span>
<span class="c1"># Copyright 2017-2018 Intel Corporation</span>
<span class="c1">#</span>
<span class="c1"># Licensed under the Apache License, Version 2.0 (the &quot;License&quot;);</span>
<span class="c1"># you may not use this file except in compliance with the License.</span>
<span class="c1"># You may obtain a copy of the License at</span>
<span class="c1">#</span>
<span class="c1">#     http://www.apache.org/licenses/LICENSE-2.0</span>
<span class="c1">#</span>
<span class="c1"># Unless required by applicable law or agreed to in writing, software</span>
<span class="c1"># distributed under the License is distributed on an &quot;AS IS&quot; BASIS,</span>
<span class="c1"># WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span>
<span class="c1"># See the License for the specific language governing permissions and</span>
<span class="c1"># limitations under the License.</span>
<span class="c1"># ******************************************************************************</span>
<span class="sd">&quot;&quot;&quot;</span>
<span class="sd">Utilities for working with the local dataset cache.</span>
<span class="sd">&quot;&quot;&quot;</span>
<span class="kn">import</span> <span class="nn">os</span>
<span class="kn">import</span> <span class="nn">logging</span>
<span class="kn">import</span> <span class="nn">shutil</span>
<span class="kn">import</span> <span class="nn">tempfile</span>
<span class="kn">import</span> <span class="nn">json</span>
<span class="kn">from</span> <span class="nn">urllib.parse</span> <span class="kn">import</span> <span class="n">urlparse</span>
<span class="kn">from</span> <span class="nn">pathlib</span> <span class="kn">import</span> <span class="n">Path</span>
<span class="kn">from</span> <span class="nn">typing</span> <span class="kn">import</span> <span class="n">Tuple</span><span class="p">,</span> <span class="n">Union</span><span class="p">,</span> <span class="n">IO</span>
<span class="kn">from</span> <span class="nn">hashlib</span> <span class="kn">import</span> <span class="n">sha256</span>

<span class="kn">from</span> <span class="nn">nlp_architect</span> <span class="kn">import</span> <span class="n">LIBRARY_OUT</span>
<span class="kn">from</span> <span class="nn">nlp_architect.utils.io</span> <span class="kn">import</span> <span class="n">load_json_file</span>

<span class="kn">import</span> <span class="nn">requests</span>

<span class="n">logger</span> <span class="o">=</span> <span class="n">logging</span><span class="o">.</span><span class="n">getLogger</span><span class="p">(</span><span class="vm">__name__</span><span class="p">)</span>  <span class="c1"># pylint: disable=invalid-name</span>

<span class="n">MODEL_CACHE</span> <span class="o">=</span> <span class="n">LIBRARY_OUT</span> <span class="o">/</span> <span class="s2">&quot;pretrained_models&quot;</span>


<div class="viewcode-block" id="cached_path"><a class="viewcode-back" href="../../../generated_api/nlp_architect.utils.html#nlp_architect.utils.file_cache.cached_path">[docs]</a><span class="k">def</span> <span class="nf">cached_path</span><span class="p">(</span><span class="n">url_or_filename</span><span class="p">:</span> <span class="n">Union</span><span class="p">[</span><span class="nb">str</span><span class="p">,</span> <span class="n">Path</span><span class="p">],</span> <span class="n">cache_dir</span><span class="p">:</span> <span class="nb">str</span> <span class="o">=</span> <span class="kc">None</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="nb">str</span><span class="p">:</span>
    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Given something that might be a URL (or might be a local path),</span>
<span class="sd">    determine which. If it&#39;s a URL, download the file and cache it, and</span>
<span class="sd">    return the path to the cached file. If it&#39;s already a local path,</span>
<span class="sd">    make sure the file exists and then return the path.</span>
<span class="sd">    &quot;&quot;&quot;</span>
    <span class="k">if</span> <span class="n">cache_dir</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span>
        <span class="n">cache_dir</span> <span class="o">=</span> <span class="n">MODEL_CACHE</span>
    <span class="k">else</span><span class="p">:</span>
        <span class="n">cache_dir</span> <span class="o">=</span> <span class="n">cache_dir</span>
    <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">url_or_filename</span><span class="p">,</span> <span class="n">Path</span><span class="p">):</span>
        <span class="n">url_or_filename</span> <span class="o">=</span> <span class="nb">str</span><span class="p">(</span><span class="n">url_or_filename</span><span class="p">)</span>

    <span class="n">parsed</span> <span class="o">=</span> <span class="n">urlparse</span><span class="p">(</span><span class="n">url_or_filename</span><span class="p">)</span>

    <span class="k">if</span> <span class="n">parsed</span><span class="o">.</span><span class="n">scheme</span> <span class="ow">in</span> <span class="p">(</span><span class="s2">&quot;http&quot;</span><span class="p">,</span> <span class="s2">&quot;https&quot;</span><span class="p">):</span>
        <span class="c1"># URL, so get it from the cache (downloading if necessary)</span>
        <span class="k">return</span> <span class="n">get_from_cache</span><span class="p">(</span><span class="n">url_or_filename</span><span class="p">,</span> <span class="n">cache_dir</span><span class="p">)</span>
    <span class="k">if</span> <span class="n">os</span><span class="o">.</span><span class="n">path</span><span class="o">.</span><span class="n">exists</span><span class="p">(</span><span class="n">url_or_filename</span><span class="p">):</span>
        <span class="c1"># File, and it exists.</span>
        <span class="nb">print</span><span class="p">(</span><span class="s2">&quot;File already exists. No further processing needed.&quot;</span><span class="p">)</span>
        <span class="k">return</span> <span class="n">url_or_filename</span>
    <span class="k">if</span> <span class="n">parsed</span><span class="o">.</span><span class="n">scheme</span> <span class="o">==</span> <span class="s2">&quot;&quot;</span><span class="p">:</span>
        <span class="c1"># File, but it doesn&#39;t exist.</span>
        <span class="k">raise</span> <span class="ne">FileNotFoundError</span><span class="p">(</span><span class="s2">&quot;file </span><span class="si">{}</span><span class="s2"> not found&quot;</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">url_or_filename</span><span class="p">))</span>

    <span class="c1"># Something unknown</span>
    <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">&quot;unable to parse </span><span class="si">{}</span><span class="s2"> as a URL or as a local path&quot;</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">url_or_filename</span><span class="p">))</span></div>


<div class="viewcode-block" id="url_to_filename"><a class="viewcode-back" href="../../../generated_api/nlp_architect.utils.html#nlp_architect.utils.file_cache.url_to_filename">[docs]</a><span class="k">def</span> <span class="nf">url_to_filename</span><span class="p">(</span><span class="n">url</span><span class="p">:</span> <span class="nb">str</span><span class="p">,</span> <span class="n">etag</span><span class="p">:</span> <span class="nb">str</span> <span class="o">=</span> <span class="kc">None</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="nb">str</span><span class="p">:</span>
    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Convert `url` into a hashed filename in a repeatable way.</span>
<span class="sd">    If `etag` is specified, append its hash to the url&#39;s, delimited</span>
<span class="sd">    by a period.</span>
<span class="sd">    &quot;&quot;&quot;</span>
    <span class="k">if</span> <span class="n">url</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s2">&quot;/&quot;</span><span class="p">)[</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span><span class="o">.</span><span class="n">endswith</span><span class="p">(</span><span class="s2">&quot;zip&quot;</span><span class="p">):</span>
        <span class="n">url_bytes</span> <span class="o">=</span> <span class="n">url</span><span class="o">.</span><span class="n">encode</span><span class="p">(</span><span class="s2">&quot;utf-8&quot;</span><span class="p">)</span>
        <span class="n">url_hash</span> <span class="o">=</span> <span class="n">sha256</span><span class="p">(</span><span class="n">url_bytes</span><span class="p">)</span>
        <span class="n">filename</span> <span class="o">=</span> <span class="n">url_hash</span><span class="o">.</span><span class="n">hexdigest</span><span class="p">()</span>
        <span class="k">if</span> <span class="n">etag</span><span class="p">:</span>
            <span class="n">etag_bytes</span> <span class="o">=</span> <span class="n">etag</span><span class="o">.</span><span class="n">encode</span><span class="p">(</span><span class="s2">&quot;utf-8&quot;</span><span class="p">)</span>
            <span class="n">etag_hash</span> <span class="o">=</span> <span class="n">sha256</span><span class="p">(</span><span class="n">etag_bytes</span><span class="p">)</span>
            <span class="n">filename</span> <span class="o">+=</span> <span class="s2">&quot;.&quot;</span> <span class="o">+</span> <span class="n">etag_hash</span><span class="o">.</span><span class="n">hexdigest</span><span class="p">()</span>
    <span class="k">else</span><span class="p">:</span>
        <span class="n">filename</span> <span class="o">=</span> <span class="n">url</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s2">&quot;/&quot;</span><span class="p">)[</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span>

    <span class="k">return</span> <span class="n">filename</span></div>


<div class="viewcode-block" id="filename_to_url"><a class="viewcode-back" href="../../../generated_api/nlp_architect.utils.html#nlp_architect.utils.file_cache.filename_to_url">[docs]</a><span class="k">def</span> <span class="nf">filename_to_url</span><span class="p">(</span><span class="n">filename</span><span class="p">:</span> <span class="nb">str</span><span class="p">,</span> <span class="n">cache_dir</span><span class="p">:</span> <span class="nb">str</span> <span class="o">=</span> <span class="kc">None</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="n">Tuple</span><span class="p">[</span><span class="nb">str</span><span class="p">,</span> <span class="nb">str</span><span class="p">]:</span>
    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Return the url and etag (which may be ``None``) stored for `filename`.</span>
<span class="sd">    Raise ``FileNotFoundError`` if `filename` or its stored metadata do not exist.</span>
<span class="sd">    &quot;&quot;&quot;</span>
    <span class="k">if</span> <span class="n">cache_dir</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span>
        <span class="n">cache_dir</span> <span class="o">=</span> <span class="n">MODEL_CACHE</span>

    <span class="n">cache_path</span> <span class="o">=</span> <span class="n">os</span><span class="o">.</span><span class="n">path</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">cache_dir</span><span class="p">,</span> <span class="n">filename</span><span class="p">)</span>
    <span class="k">if</span> <span class="ow">not</span> <span class="n">os</span><span class="o">.</span><span class="n">path</span><span class="o">.</span><span class="n">exists</span><span class="p">(</span><span class="n">cache_path</span><span class="p">):</span>
        <span class="k">raise</span> <span class="ne">FileNotFoundError</span><span class="p">(</span><span class="s2">&quot;file </span><span class="si">{}</span><span class="s2"> not found&quot;</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">cache_path</span><span class="p">))</span>

    <span class="n">meta_path</span> <span class="o">=</span> <span class="n">cache_path</span> <span class="o">+</span> <span class="s2">&quot;.json&quot;</span>
    <span class="k">if</span> <span class="ow">not</span> <span class="n">os</span><span class="o">.</span><span class="n">path</span><span class="o">.</span><span class="n">exists</span><span class="p">(</span><span class="n">meta_path</span><span class="p">):</span>
        <span class="k">raise</span> <span class="ne">FileNotFoundError</span><span class="p">(</span><span class="s2">&quot;file </span><span class="si">{}</span><span class="s2"> not found&quot;</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">meta_path</span><span class="p">))</span>

    <span class="k">with</span> <span class="nb">open</span><span class="p">(</span><span class="n">meta_path</span><span class="p">)</span> <span class="k">as</span> <span class="n">meta_file</span><span class="p">:</span>
        <span class="n">metadata</span> <span class="o">=</span> <span class="n">json</span><span class="o">.</span><span class="n">load</span><span class="p">(</span><span class="n">meta_file</span><span class="p">)</span>
    <span class="n">url</span> <span class="o">=</span> <span class="n">metadata</span><span class="p">[</span><span class="s2">&quot;url&quot;</span><span class="p">]</span>
    <span class="n">etag</span> <span class="o">=</span> <span class="n">metadata</span><span class="p">[</span><span class="s2">&quot;etag&quot;</span><span class="p">]</span>

    <span class="k">return</span> <span class="n">url</span><span class="p">,</span> <span class="n">etag</span></div>


<div class="viewcode-block" id="http_get"><a class="viewcode-back" href="../../../generated_api/nlp_architect.utils.html#nlp_architect.utils.file_cache.http_get">[docs]</a><span class="k">def</span> <span class="nf">http_get</span><span class="p">(</span><span class="n">url</span><span class="p">:</span> <span class="nb">str</span><span class="p">,</span> <span class="n">temp_file</span><span class="p">:</span> <span class="n">IO</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="kc">None</span><span class="p">:</span>
    <span class="n">req</span> <span class="o">=</span> <span class="n">requests</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">url</span><span class="p">,</span> <span class="n">stream</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
    <span class="k">for</span> <span class="n">chunk</span> <span class="ow">in</span> <span class="n">req</span><span class="o">.</span><span class="n">iter_content</span><span class="p">(</span><span class="n">chunk_size</span><span class="o">=</span><span class="mi">1024</span><span class="p">):</span>
        <span class="k">if</span> <span class="n">chunk</span><span class="p">:</span>  <span class="c1"># filter out keep-alive new chunks</span>
            <span class="n">temp_file</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="n">chunk</span><span class="p">)</span></div>


<div class="viewcode-block" id="get_from_cache"><a class="viewcode-back" href="../../../generated_api/nlp_architect.utils.html#nlp_architect.utils.file_cache.get_from_cache">[docs]</a><span class="k">def</span> <span class="nf">get_from_cache</span><span class="p">(</span><span class="n">url</span><span class="p">:</span> <span class="nb">str</span><span class="p">,</span> <span class="n">cache_dir</span><span class="p">:</span> <span class="nb">str</span> <span class="o">=</span> <span class="kc">None</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="nb">str</span><span class="p">:</span>
    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Given a URL, look for the corresponding dataset in the local cache.</span>
<span class="sd">    If it&#39;s not there, download it. Then return the path to the cached file.</span>
<span class="sd">    &quot;&quot;&quot;</span>
    <span class="k">if</span> <span class="n">cache_dir</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span>
        <span class="n">cache_dir</span> <span class="o">=</span> <span class="n">MODEL_CACHE</span>

    <span class="n">os</span><span class="o">.</span><span class="n">makedirs</span><span class="p">(</span><span class="n">cache_dir</span><span class="p">,</span> <span class="n">exist_ok</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>

    <span class="n">response</span> <span class="o">=</span> <span class="n">requests</span><span class="o">.</span><span class="n">head</span><span class="p">(</span><span class="n">url</span><span class="p">,</span> <span class="n">allow_redirects</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
    <span class="k">if</span> <span class="n">response</span><span class="o">.</span><span class="n">status_code</span> <span class="o">!=</span> <span class="mi">200</span><span class="p">:</span>
        <span class="k">raise</span> <span class="ne">IOError</span><span class="p">(</span>
            <span class="s2">&quot;HEAD request failed for url </span><span class="si">{}</span><span class="s2"> with status code </span><span class="si">{}</span><span class="s2">&quot;</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">url</span><span class="p">,</span> <span class="n">response</span><span class="o">.</span><span class="n">status_code</span><span class="p">)</span>
        <span class="p">)</span>
    <span class="n">etag</span> <span class="o">=</span> <span class="n">response</span><span class="o">.</span><span class="n">headers</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">&quot;ETag&quot;</span><span class="p">)</span>

    <span class="n">filename</span> <span class="o">=</span> <span class="n">url_to_filename</span><span class="p">(</span><span class="n">url</span><span class="p">,</span> <span class="n">etag</span><span class="p">)</span>

    <span class="c1"># get cache path to put the file</span>
    <span class="n">cache_path</span> <span class="o">=</span> <span class="n">os</span><span class="o">.</span><span class="n">path</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">cache_dir</span><span class="p">,</span> <span class="n">filename</span><span class="p">)</span>

    <span class="n">need_downloading</span> <span class="o">=</span> <span class="kc">True</span>

    <span class="k">if</span> <span class="n">os</span><span class="o">.</span><span class="n">path</span><span class="o">.</span><span class="n">exists</span><span class="p">(</span><span class="n">cache_path</span><span class="p">):</span>
        <span class="c1"># check if etag has changed comparing with the metadata</span>
        <span class="k">if</span> <span class="n">url</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s2">&quot;/&quot;</span><span class="p">)[</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span><span class="o">.</span><span class="n">endswith</span><span class="p">(</span><span class="s2">&quot;zip&quot;</span><span class="p">):</span>
            <span class="n">meta_path</span> <span class="o">=</span> <span class="n">cache_path</span> <span class="o">+</span> <span class="s2">&quot;.json&quot;</span>
        <span class="k">else</span><span class="p">:</span>
            <span class="n">meta_path</span> <span class="o">=</span> <span class="n">cache_path</span> <span class="o">+</span> <span class="s2">&quot;_meta_&quot;</span> <span class="o">+</span> <span class="s2">&quot;.json&quot;</span>
        <span class="n">meta</span> <span class="o">=</span> <span class="n">load_json_file</span><span class="p">(</span><span class="n">meta_path</span><span class="p">)</span>
        <span class="k">if</span> <span class="n">meta</span><span class="p">[</span><span class="s2">&quot;etag&quot;</span><span class="p">]</span> <span class="o">==</span> <span class="n">etag</span><span class="p">:</span>
            <span class="nb">print</span><span class="p">(</span><span class="s2">&quot;file already present&quot;</span><span class="p">)</span>
            <span class="n">need_downloading</span> <span class="o">=</span> <span class="kc">False</span>

    <span class="k">if</span> <span class="n">need_downloading</span><span class="p">:</span>
        <span class="nb">print</span><span class="p">(</span><span class="s2">&quot;File not present or etag changed&quot;</span><span class="p">)</span>
        <span class="c1"># Download to temporary file, then copy to cache dir once finished.</span>
        <span class="c1"># Otherwise you get corrupt cache entries if the download gets interrupted.</span>
        <span class="k">with</span> <span class="n">tempfile</span><span class="o">.</span><span class="n">NamedTemporaryFile</span><span class="p">()</span> <span class="k">as</span> <span class="n">temp_file</span><span class="p">:</span>
            <span class="n">logger</span><span class="o">.</span><span class="n">info</span><span class="p">(</span><span class="s2">&quot;</span><span class="si">%s</span><span class="s2"> not found in cache, downloading to </span><span class="si">%s</span><span class="s2">&quot;</span><span class="p">,</span> <span class="n">url</span><span class="p">,</span> <span class="n">temp_file</span><span class="o">.</span><span class="n">name</span><span class="p">)</span>

            <span class="c1"># GET file object</span>
            <span class="n">http_get</span><span class="p">(</span><span class="n">url</span><span class="p">,</span> <span class="n">temp_file</span><span class="p">)</span>

            <span class="c1"># we are copying the file before closing it, so flush to avoid truncation</span>
            <span class="n">temp_file</span><span class="o">.</span><span class="n">flush</span><span class="p">()</span>
            <span class="c1"># shutil.copyfileobj() starts at the current position, so go to the start</span>
            <span class="n">temp_file</span><span class="o">.</span><span class="n">seek</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span>

            <span class="n">logger</span><span class="o">.</span><span class="n">info</span><span class="p">(</span><span class="s2">&quot;copying </span><span class="si">%s</span><span class="s2"> to cache at </span><span class="si">%s</span><span class="s2">&quot;</span><span class="p">,</span> <span class="n">temp_file</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">cache_path</span><span class="p">)</span>
            <span class="k">with</span> <span class="nb">open</span><span class="p">(</span><span class="n">cache_path</span><span class="p">,</span> <span class="s2">&quot;wb&quot;</span><span class="p">)</span> <span class="k">as</span> <span class="n">cache_file</span><span class="p">:</span>
                <span class="n">shutil</span><span class="o">.</span><span class="n">copyfileobj</span><span class="p">(</span><span class="n">temp_file</span><span class="p">,</span> <span class="n">cache_file</span><span class="p">)</span>

            <span class="n">logger</span><span class="o">.</span><span class="n">info</span><span class="p">(</span><span class="s2">&quot;creating metadata file for </span><span class="si">%s</span><span class="s2">&quot;</span><span class="p">,</span> <span class="n">cache_path</span><span class="p">)</span>
            <span class="n">meta</span> <span class="o">=</span> <span class="p">{</span><span class="s2">&quot;url&quot;</span><span class="p">:</span> <span class="n">url</span><span class="p">,</span> <span class="s2">&quot;etag&quot;</span><span class="p">:</span> <span class="n">etag</span><span class="p">}</span>
            <span class="k">if</span> <span class="n">url</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s2">&quot;/&quot;</span><span class="p">)[</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span><span class="o">.</span><span class="n">endswith</span><span class="p">(</span><span class="s2">&quot;zip&quot;</span><span class="p">):</span>
                <span class="n">meta_path</span> <span class="o">=</span> <span class="n">cache_path</span> <span class="o">+</span> <span class="s2">&quot;.json&quot;</span>
            <span class="k">else</span><span class="p">:</span>
                <span class="n">meta_path</span> <span class="o">=</span> <span class="n">cache_path</span> <span class="o">+</span> <span class="s2">&quot;_meta_&quot;</span> <span class="o">+</span> <span class="s2">&quot;.json&quot;</span>
            <span class="k">with</span> <span class="nb">open</span><span class="p">(</span><span class="n">meta_path</span><span class="p">,</span> <span class="s2">&quot;w&quot;</span><span class="p">)</span> <span class="k">as</span> <span class="n">meta_file</span><span class="p">:</span>
                <span class="n">json</span><span class="o">.</span><span class="n">dump</span><span class="p">(</span><span class="n">meta</span><span class="p">,</span> <span class="n">meta_file</span><span class="p">)</span>

            <span class="n">logger</span><span class="o">.</span><span class="n">info</span><span class="p">(</span><span class="s2">&quot;removing temp file </span><span class="si">%s</span><span class="s2">&quot;</span><span class="p">,</span> <span class="n">temp_file</span><span class="o">.</span><span class="n">name</span><span class="p">)</span>

    <span class="k">return</span> <span class="n">cache_path</span><span class="p">,</span> <span class="n">need_downloading</span></div>
</pre></div>

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